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When water vapor (a gas) cools and changes back into a liquid, creating clouds.
Heat from the sun changes liquid water to water vapor as it rises into the atmosphere.
Any form of water (rain, snow, hail, sleet or mist)falling to earth.
Water moving downhill to lakes, rivers, oceans, etc. or soaking into ground water.
The continuous process by which water moves from Earth's surface to the atmosphere and back.
Evaporation from the leaves and stems of plants.